Thytronic Pro-N NVA100X-D

APPENDIX
347
NVA100X-D - Manual - 02 - 2016
Phase overcurrent 50/51 side H and side L - Extremely inverse time curve (ANSI/IEEE type EI)—
F_51-ANSIEI-Char.ai
1.1
2 3 4 5 6 7 8 9 10 20
0.01
0.1
1
10
100
1000
10000
t [s]
10 s
60 s
5 s
0.5 s
1 s
0.2 s
0.1 s
0.02 s
t =
t
(H)
>
inv
·
[(I/I
(H)
>
inv
)
2
-1]
5.64
+ 0.024
t =
t
(L)
>
inv
·
[(I/I
(L)
>
inv
)
2
-1]
5.64
+ 0.024
Note: match of operating and setting time takes place when I/I
(H)
>
inv
or I/I
(L)
>
inv
= 2.789
I /I
(H)
>inv
I /I
(L)
>inv
t
(H)
>
inv
t
(L)
>
inv